Problem: Simplify the following expression: $y = \dfrac{x}{7x - 9} + \dfrac{-4x - 7}{7x - 9}$
Since the expressions have the same denominator we simply combine the numerators: $y = \dfrac{x - 4x - 7}{7x - 9}$ Combine like terms: $y = \dfrac{-3x - 7}{7x - 9}$